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    RS232 to keyboard converter

    Hi, if you look at forums above, you wil see may post with C source for the 16F628 controller, i think this is a good solution, 16F84 not have a hardware RS and this may be a problem for you, because you not have a experience in to the uC. The ideais o generate fixed time delay, on 1200 b/ps you...
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    Some kind of RPM counter

    Hi, yes you can use 555 or something other chip, actually 55 may be not a very suitable for this application. I know that exist, but never not use a on chip converter, this is small chip that convert frequency to voltag. Ok i will see for some good analog decision that is not a very expensive...
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    Some kind of RPM counter

    Hi, Yes, the LM393 for example, but you must have a hysteresis.
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    Some kind of RPM counter

    Hi, you need a frequency meter mode, with 1 Hz time for measuring. See the attached file, only i'm not suare how must set the channel, if may be you can connect to input together, to be sure that every time will measure the signal. And .... im not suare if the chip have a current limit for the...
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    Some kind of RPM counter

    Hi, the ICM7226 is the most simple decisiaon, this or somethin like this chip. The next possibility is to use the uControler, in the web yu can find many diagram with PIC 16F84. But for this you must have programer etc. Another way is to use frquency to voltage converter, and use the standad...
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    Some kind of RPM counter

    Hi, OK, in this case +/- 5% you can use counter mode, because if you want high precision you must measure impulse time, and for this some suitable is uControler, but in your case this is unnecessary. You can use something like a ICM7226. For sensor, in this case using of reflective sensors is...
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    Some kind of RPM counter

    Hi, yes LED and phototransistor is ideal for this application, but if this disk is not very wide, you can use optocoupler with air gap, like a this in some PC mouse. If this disk is made from metal, steel or other magnetich material, also you can use the hall sensor. For counting have different...
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    Switching polarity of motor

    And don't forgot that not all DC motors can be reversed only with change power supply. Depend of the construction: permanent magnetic, parallel or serial stator you must change poliarity of the rotor or stator or both of them.
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    RS232 to keyboard converter

    Hi leowjunwei, i not forgot, but i just change the file in my previews post, but i will atach the file to this post too. RS_PS2.pdf
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    need help designing a power supply 3.6V 10A

    Hi, If you have a +5 you must use exactly this to make 3.6, no any reason to make 4 and then from 4 make 3.6.  In post above this 0.4 V is the differences between input and output, the 0.4 V is a very small difference, many of good DC-DC chips work with different around 0.8 V, but if you have a...
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    RS232 to keyboard converter

    Hi, Happy new year to All. About schematic, i change the file, in this file i think have not more errors :)
  12. T

    RS232 to keyboard converter

    Hi, today i have a long flight, i think will find some time to make explain more in details, but this will be later. Edit. OK, i make the simulation on 19200 bps, you talk a keyboard rate around 20 Khz. In this circuit i not store data, i transfer it on every bit, and output bt rate is connect...
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    RS232 to keyboard converter

    Hi, pleasesee the attachment. I not have a time to real test this circuit, i made only computer simulation. Tx is the input, you must have MAX232 befor this schem or some other level converter. Xtal is input for sampling, this can be on chip generator, or simple quartz generator whit invertor...
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    RS232 to keyboard converter

    Hi, i will try to make some simple, only with logic, but if look for a simple schem, then you must know that have a very big possibility to wrong data transfer. The most simple is if you have the clock generator, when detect start bit will starting sampling on every clock impulse, and this...
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    RS232 to keyboard converter

    Hi, you want to produce this device, this is right. If i am right, then you have a need from : 1. Low price 2. EMC certification 3. Reliability 4. Easy to use and compatibility to another devices 1. Low price, this depend from size and numbers of components. For example one microcontroller have...
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    Transmitter and Reciever

    Hi, do you may be a bit more particular. The Receiver and Transmiter is a only name for device that receive and transmit data, analog or digital. Ok, you talk about PIC, then may be you need a digital, but what type RS232, RS485, RF, IR, CAN ...etc
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    RS232 to keyboard converter

    Hi, RTS,CTS, DTR,DSR - this is the signals witch you can control, actually only RTS and DTR is the outputs. You can control directly these outputs from your software. You can use the first to generate the clock and the second to generate the data stream. See the attachment, this is the schem...
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    PIC 16F877 PROGRAMMING IN C

    What type of compiler you have? You must have a samples in your compiler. If you need some info about C look for ANSI C books.Also you must read very carefully the processor data sheet. When you have a real task, please write what is the difficult for you, and i believe that will have a many...
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    RS232 to keyboard converter

    Hi, i find 20 minutes and made something for you, but i can't test because have not the PS2. I use PIC16F628, below you can find the HEX, and asm. PIN 7 is the recive form MAX232 PIN 17 is the Clock PIN 18 is the Data Tomorrow, i try to find a time to draw the schecm, but this is standard PIC...
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    RS232 to keyboard converter

    Hi, yes, of course you can use standard IC but this will be very big and complex circuit diagram. I prefer to use the microcontrollers. I am have no a complete driver for a PS2 keyboard, but can ask some friend. If this is your software, i can suggest something other, why dont use RTS/CTS...
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